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An evaluation of the agreement between photointerpretation- and LiDARbased estimates of canopy cover was performed using 397 90 x 90 m reference areas in Oregon. It was determined that at low canopy cover levels LiDAR estimates tend to exceed those from photointerpretation and that this tendency reverses at high canopy cover levels. Characteristics of the airborne...

Repeatability was estimated for constitutive oleoresin yield measurements in 10 stands of three species of pines native to southeastern United States. Trees of these species that discharge large quantities of oleoresin upon wounding are considered to be most resistant to attack by southern pine beetle (Dendroctonus frontalis Zimmermann). Oleoresin...

A study of forest stand canopy variable assessment using digital, airborne, multispectral imagery is presented. Variable estimation involves stem density, canopy closure, and mean crown diameter, and it is based on quantification of spatial autocorrelation among pixel digital numbers (DN) using variogram analysis and an alternative, non-parametric approach known as...

Site Index (SI), a key inventory parameter, is traditionally estimated by using costly and laborious field assessments of tree height and age. The increasing availability of reliable information on stand initiation timing and extent of planted, even-aged stands maintained in digital databases suggests that information on the height of dominant trees suffices for...

We examine the accuracy of tree height estimates obtained via light detection and ranging (LiDAR) in a temperate rainforest characterized by complex terrain, steep slopes, and high canopy cover. The evaluation was based on precise top and base locations for > 1,000 trees in 45 plots distributed across three forest types, a dense network of ground elevation...

In southern pines of the United States, resistance to attack by southern pine beetle, Dendroctonus frontalis Zimmermann, is believed to principally involve flow of oleoresin to beetle attack sites. Both environmental and genetic factors are known to affect the quantity of oleoresin flow in loblolly pine, Pinus taeda L., but little...

A critical component of a growth and yield simulator is an estimate of mortality rates. The mortality models presented here are developed from long-term permanent plots in provinces from throughout the geographic range of ponderosa pine in the United States extending from the Black Hills of South Dakota to the Pacific Coast. The study had two objectives: estimation of...

This article reports on the development of accelerated laboratory methods to allow estimation of preservative leaching frompressure-treated wood exposed to precipitation. End-matched lumber specimens were pressure-treated with a boron?copper formulation and exposed to natural weathering for 1 yr, laboratory immersion protocols, or a laboratory-simulated rainfall...

Why are forest managers interested in quantifying maximum stand density? Nearly all conceivable management objectives dictate a stand density less than a biological maximum. Certainly, the notion that thinning dense stands increases growth on the remaining trees and reduces mortality is well-established in the literature. The interest in quantifying maximum stand...

Sudden oak death, a disease associated with the pathogen Phytophthora ramorum, has a large number of shrub and tree host species. Three of the tree species must susceptible to mortality from the disease, California black oak (Quercus kelloggii), coast live oak (Quercus agrifolia), and tanoak (...

The equations presented predict crown area for 13 species of trees and shrubs which may be found growing in competition with commercial conifers during early stages of stand development. The equations express crown area as a function of basal area and height. Parameters were estimated for each species individually using weighted nonlinear least square regression.

Data from the Women's Health Initiative were used to quantify the relationship between the loss of trees to an invasive forest pest?the emerald ash borer?and cardiovascular disease. We estimated semi- parametric Cox proportional hazards model of time to cardiovascular disease, adjusting for confounders. We defined the incidence of cardiovascular disease as acute...

National forests have a wealth of natural amenities that attract over 175 million recreational visitors a year. Although natural amenities draw visitors to national forests, many of the recreational activities that they engage in require built amenities, such as roads, campgrounds, boat ramps, and trails. We estimate regression models of the effect of two common built...

Polycyclic aromatic hydrocarbons (PAHs) are a class of air pollutants linked to a wide range of adverse health outcomes, including asthma, cancers, cardiovascular disease, and fetal growth impairment. PAHs are emitted by combustion of organic matter (e.g. fossil fuels, plant biomass) and can accumulate in plant and animal tissues over time. Compared to criteria...

Tree-killing species of the Scolytidae (Coleoptera) must locate suitable hosts at least once per generation for successful reproduction. The process used to select hosts is complex, involving a sequence of steps and many possible outcomes. Because more beetles land on bark (host-find) than bore galleries (host-recognize), postlanding behaviors appear to be important in...

Microsatellite and RAPD markers suggest that American chestnut exists as a highly variable species. Even at the margins of its natural range, with a large proportion of its genetic variability occurring within populations (~95%). A statistically significant proportion also exists among population. Although genetic differentiation among populations has taken place, no...

In: Restoration of American Chestnut to Forest Lands: proceedings of a conference and workshop held at The North Carolina Arboretum, Asheville, North Carolina, U. S. A., May 4–6, 2004. Natural Resources Report NPS/NCR/CUE/NRR – 2006/001. [Washington, D.C.]: U.S. Dept. of the Interior, National Park Service, National Capital Region, Center for Urban Ecology, 2006: 109-122

A height increment model is developed and evaluated for individual trees of ponderosa pine throughout the species range in western United States. The data set used in this study came from long-term permanent research plots in even-aged, pure stands both planted and of natural origin. The data base consists of six levels-of-growing stock studies supplemented by initial...

A height increment equation was used to determine the effects of site quality and competing herbaceous vegetation on the development of ponderosa pine seedlings (Pinus ponderosa var. scopulorum Engelm.). Study areas were established in 36 plantations across northwest and west-central Montana on Champion International Corporation's timberland (...

Light detection and ranging (LiDAR), also known as airborne laser scanning, is a rapidly emerging technology for remote sensing. Used to help map, monitor, and assess natural resources, LiDAR data were first embraced by forestry professionals in Scandinavia as a tool for conducting forest inventories in the mid to late 1990s. Thus early LiDAR theory and applications...

Current standardized methods are not well-suited for estimating in-service preservative leaching from treated wood products. This study compared several alternative leaching methods to a commonly used standard method, and to leaching under natural exposure conditions. Small blocks or lumber specimens were pressure treated with a wood preservative containing borax and...